1. Field
Apparatuses and methods consistent with exemplary embodiments relate to image processing, and more particularly, to an apparatus and method for separating an image into foreground and background.
2. Description of the Related Art
Currently, while interest in and desire for security increases, image monitoring systems that is historically used in application-specific areas, such as military and police stations are becoming more commercialized and are gradually being supplied to non-governmental corporations and households. Due to the expanding sizes of areas being monitored, there has been an increase in personnel cost for providing additional monitoring manpower; and according to data from psychological studies, when tasked with monitoring such expanded-sized areas, it has also become more difficult for said manpower to provide the proper amount of attention in any given situation. Therefore, the demand for automation in intrusion detection has increased.
In an automated intrusion detection system, one of the main functions of an intelligent monitoring system is extracting a foreground area from an input image. People or vehicles, which are the main interesting objects, correspond to an interesting foreground of a monitoring system. However, people or vehicles generally move and thus a moving part and a non-moving part are separated from each other in an image so that foreground, that is, people or vehicles, are extracted.
In general methods of extracting foreground from an image, color information (grey tone information) of the image is used. A general method of separating foreground/background, which is based on a color value, is sensitive to a change in lighting. Thus, a shadow part is detected as foreground, as illustrated in FIG. 1B, with respect to an original image of FIG. 1A. However, in the general method of separating foreground/background based on a color value, when a still object in an original image of FIG. 2A moves, as in FIG. 2B, an area in which a object was in the still state (i.e., in FIG. 2A) is also detected as part of a foreground area, as illustrated in FIG. 2C. Thus, such general methods are limited in their effectiveness.